PA film
- Left hilum "never" lower than right
- Left hilum usually more prominent
- CTR = max heart vs max internal (rib to rib) chest diam
- Both domes and heart borders clear?
- RHB indistinct = RML
- LHB indistinct = LUL
- Rt diaphragm indistinct = RLL
- Lt diaphragm (medially) = LLL
CXR Lateral
Lat CXR
- Lower T spine darker than upper
- Whole right diaphragm visible
- Left visible from cardiac shadow to costophrenic recess
Upper mediastinum: 1st rib to betw angle of Louis & T4
- Upper reaches of all in lower mediastimum
Lower mediastimun divided into 3:
Ant ⅓: Body sternum to pericardium:
- Thymus
- Nodes
- Internal thoracic vessels
Mid ⅓: Pericardium:
- Heart/Pericardial sac
- Origins great vessesl
- Tracheal bifurcation
Post ⅓ Pericardium to vertebrae:
- Descending aorta/branches
- Azygos /hemiazygos venous veins
- Thoracic duct ∓ cisterna chyli
- Oesophagus
- Vagus & splanchnic nerves
CXR lateral
Ant mediastinal mass (4Ts)
- Thymoma (Ca++, 15% have myaesthenia gravis)
- Teratoma
- Thyroid
- Terrible Lymphoma
Pulmonary oedema
CXR signs
- Upper lobe diversion (distended cf normal)
- Kerley B line (1cm long lat subpleural, interstitial fluid)
- Cardiomegaly
- Batwing (peripheral sparing) oedema
- Peribronchial cuffing (airway oedema)
- Pleural effusions
Pulm. Oedema DDx
- ARDS
- Pulm. haemorrhage
- Atypical pneumonia e.g. fungal, PCP
Fibrosis
Lower lobe fibrosis
SCAR
Systemic sclerosis
Cryptogenic fibrosing alveolitis
Asbestosis
Rheumatoid arthritis
Upper lobe fibrosis
BREASTS+C
Beryllium
Radiation
Extrinsic allergic alveolitis
Ankylosing spondylitis
Sarcoidosis
TB
Scoliosis
Coal workers pneumoconiosis